Increase and decrease evenly calculator
Tell it how many stitches you have and how many to add or remove. It spaces them out and writes the row for you, for knitting or crochet, flat or in the round.
How to use it
- Choose knitting or crochet, and whether you are increasing or decreasing.
- Enter the stitches on your needle or hook now, then how many to add or remove. Patterns often say "increase 12 sts evenly across".
- Pick how you work: flat in rows, or in the round. For knitting increases, pick M1 (between stitches) or kfb (into a stitch).
- Copy the instructions. "Easiest to remember" is quicker to work; "Most even spacing" spreads the extra stitches more smoothly.
How the math works
Take 100 stitches and 12 M1 increases, worked flat. An M1 uses no stitches, so all 100 are plain knit stitches that need to be shared out between the increases. 100 ÷ 12 is 8 with 4 left over, so most gaps are 8 stitches and 4 of them get one extra.
On a flat row, one gap is split between the two edges so no increase lands on the selvedge. That gives: K4, (M1, k9) 4 times, (M1, k8) 7 times, M1, k4. Check it: 4 + 36 + 56 + 4 = 100 stitches worked, plus 12 new ones, makes 112.
Increases worked into a stitch (kfb, or 2 single crochet in one stitch) use up one stitch each, and decreases use two. The calculator subtracts those first, then shares out what is left.
Easiest to remember or most even?
The first version puts all the longer gaps together, so you repeat one sequence and then another. The second mixes long and short gaps through the row. On a sweater yoke or a hat crown the difference is hard to see; on a fine, plain fabric the even version can look smoother.
Questions
Why can I remove at most half of my stitches in one row?
Each decrease (k2tog or sc2tog) works two stitches together into one. With 40 stitches you can make at most 20 decreases, which leaves 20 stitches.
Does it work for half double or double crochet?
Yes. The stitch counts are the same for any basic stitch. Read "sc" as the stitch your pattern uses, for example "hdc 5, 2 hdc in next st".
Can I use yarn overs instead of M1?
Yes. A yarn over is also made between two stitches, so choose "Between stitches". It leaves a small hole, which some lace and raglan patterns want.
Why does the row start and end with plain stitches?
When you work flat, the calculator splits one gap across both edges. That keeps shaping off the selvedge, where it is hard to seam, and makes the row symmetrical.